mirror of
https://github.com/NixOS/nixpkgs.git
synced 2024-11-22 05:31:22 +00:00
89 lines
3.6 KiB
Nix
89 lines
3.6 KiB
Nix
/* Impure default args for `pkgs/top-level/default.nix`. See that file
|
||
for the meaning of each argument. */
|
||
|
||
with builtins;
|
||
|
||
let
|
||
|
||
homeDir = builtins.getEnv "HOME";
|
||
|
||
# Return ‘x’ if it evaluates, or ‘def’ if it throws an exception.
|
||
try = x: def: let res = tryEval x; in if res.success then res.value else def;
|
||
|
||
in
|
||
|
||
{ # We combine legacy `system` and `platform` into `localSystem`, if
|
||
# `localSystem` was not passed. Strictly speaking, this is pure desugar, but
|
||
# it is most convient to do so before the impure `localSystem.system` default,
|
||
# so we do it now.
|
||
localSystem ? builtins.intersectAttrs { system = null; platform = null; } args
|
||
|
||
, # These are needed only because nix's `--arg` command-line logic doesn't work
|
||
# with unnamed parameters allowed by ...
|
||
system ? localSystem.system
|
||
, platform ? localSystem.platform
|
||
, crossSystem ? null
|
||
|
||
, # Fallback: The contents of the configuration file found at $NIXPKGS_CONFIG or
|
||
# $HOME/.config/nixpkgs/config.nix.
|
||
config ? let
|
||
configFile = getEnv "NIXPKGS_CONFIG";
|
||
configFile2 = homeDir + "/.config/nixpkgs/config.nix";
|
||
configFile3 = homeDir + "/.nixpkgs/config.nix"; # obsolete
|
||
in
|
||
if configFile != "" && pathExists configFile then import configFile
|
||
else if homeDir != "" && pathExists configFile2 then import configFile2
|
||
else if homeDir != "" && pathExists configFile3 then import configFile3
|
||
else {}
|
||
|
||
, # Overlays are used to extend Nixpkgs collection with additional
|
||
# collections of packages. These collection of packages are part of the
|
||
# fix-point made by Nixpkgs.
|
||
overlays ? let
|
||
isDir = path: pathExists (path + "/.");
|
||
pathOverlays = try (toString <nixpkgs-overlays>) "";
|
||
homeOverlaysFile = homeDir + "/.config/nixpkgs/overlays.nix";
|
||
homeOverlaysDir = homeDir + "/.config/nixpkgs/overlays";
|
||
overlays = path:
|
||
# check if the path is a directory or a file
|
||
if isDir path then
|
||
# it's a directory, so the set of overlays from the directory, ordered lexicographically
|
||
let content = readDir path; in
|
||
map (n: import (path + ("/" + n)))
|
||
(builtins.filter (n: builtins.match ".*\\.nix" n != null || pathExists (path + ("/" + n + "/default.nix")))
|
||
(attrNames content))
|
||
else
|
||
# it's a file, so the result is the contents of the file itself
|
||
import path;
|
||
in
|
||
if pathOverlays != "" && pathExists pathOverlays then overlays pathOverlays
|
||
else if pathExists homeOverlaysFile && pathExists homeOverlaysDir then
|
||
throw ''
|
||
Nixpkgs overlays can be specified with ${homeOverlaysFile} or ${homeOverlaysDir}, but not both.
|
||
Please remove one of them and try again.
|
||
''
|
||
else if pathExists homeOverlaysFile then
|
||
if isDir homeOverlaysFile then
|
||
throw (homeOverlaysFile + " should be a file")
|
||
else overlays homeOverlaysFile
|
||
else if pathExists homeOverlaysDir then
|
||
if !(isDir homeOverlaysDir) then
|
||
throw (homeOverlaysDir + " should be a directory")
|
||
else overlays homeOverlaysDir
|
||
else []
|
||
|
||
, ...
|
||
} @ args:
|
||
|
||
# If `localSystem` was explicitly passed, legacy `system` and `platform` should
|
||
# not be passed.
|
||
assert args ? localSystem -> !(args ? system || args ? platform);
|
||
|
||
import ./. (builtins.removeAttrs args [ "system" "platform" ] // {
|
||
inherit config overlays crossSystem;
|
||
# Fallback: Assume we are building packages on the current (build, in GNU
|
||
# Autotools parlance) system.
|
||
localSystem = (if args ? localSystem then {}
|
||
else { system = builtins.currentSystem; }) // localSystem;
|
||
})
|